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MRCOOL DIY 36K BTU Wall-Mounted Air Handler | Indoor Unit for Large Spaces up to 1550 Sq. Ft.

Complete your DIY mini-split system with this high-capacity indoor air handler—designed for easy installation and smart comfort control.

Complete your large-scale DIY mini-split system with the 5th Generation MRCOOL® DIY® 36K BTU Air Handler. This powerful, wall-mounted indoor unit is engineered for spaces up to 1550 sq. ft., delivering robust heating and cooling for large living areas, open floor plans, basements, and workshops. Designed specifically to pair with a matching MRCOOL DIY 36K BTU outdoor condenser, this air handler features user-friendly technology that makes professional-grade comfort achievable through true DIY installation.

No special tools or HVAC experience needed—just pair with a compatible outdoor unit and QuickConnect lineset for a complete, high-performance system.

Key Features & Benefits

✅ High-Capacity Performance for Large Spaces
With 36,000 BTU (3-Ton) output, this air handler efficiently manages climate control in areas where standard units fall short. Ideal for great rooms, master suites, converted garages, and open-concept living areas.

✅ Designed for DIY QuickConnect® Compatibility
This indoor unit is engineered specifically for use with MRCOOL’s QuickConnect® pre-charged line sets. When paired with a compatible 36K BTU outdoor condenser, installation becomes tool-simple with no vacuum pump or refrigerant handling required.

✅ Ready for DIYPRO® Electrical Integration
Features built-in connections for the MRCOOL DIYPRO® cable (sold separately with condenser), which combines power and communication wiring into one durable, weather-resistant line—eliminating the need for separate electrical conduit.

✅ Smart, Multi-Platform Control
Operate your comfort system your way. Use the included wireless remote, adjust settings from anywhere via the SmartHVAC app (iOS/Android), or use voice commands with Amazon Alexa and Google Assistant.

✅ Follow Me Personalized Comfort
The wireless remote acts as a smart comfort sensor. When enabled, the air handler detects the remote’s location and directs airflow to maintain your preferred temperature exactly where you are in the room.

✅ Dry Mode for Humidity Control
More than just heating and cooling—this specialized function operates as a quiet dehumidifier, removing excess moisture to enhance comfort on humid days and help improve indoor air quality.

Technical Specifications

• Product: Indoor Air Handler (Wall-Mounted) | 5th Generation

• Capacity: 36,000 BTU (3-Ton) — Requires a matching 36K BTU outdoor condenser

• Recommended Coverage: Large spaces up to 1550 sq. ft.

• Connection System: QuickConnect® compatible (uses R-454B refrigerant in lineset)

• Electrical: DIYPRO® Cable ready

• Control: Wireless Remote, SmartHVAC App, Voice Control (Alexa/Google Assistant)

• Key Modes: Cooling, Heating, Fan, Dry (Dehumidify), Auto

• Special Feature: Follow Me temperature sensing

• Warranty: 5-Year Parts Warranty (indoor unit)

What's Included

• MRCOOL DIY 36K BTU Wall-Mounted Air Handler

• Wireless Remote Control

• Installation Template & Mounting Hardware

What You’ll Need to Complete Your System (Sold Separately)

• MRCOOL DIY 36K BTU Outdoor Condenser (5th Gen recommended)

• MRCOOL DIY QuickConnect® Pre-Charged Line Set (25 ft or required length)

• MRCOOL DIYPRO® Electrical Cable

• Condenser Pad or Wall Bracket

• Line Hide Cover Kit (recommended for clean installation)

• Electrical Disconnect Box (per local code)

Warranty & Durability

• 5-Year Parts Warranty on this indoor air handler

• Designed to pair with outdoor condensers featuring Gold Fin® corrosion-resistant technology for enhanced durability in coastal or high-humidity environments

• Part of a system backed by MRCOOL’s comprehensive warranty package, including a 7-Year Compressor Warranty and Limited Lifetime Warranty on the outdoor coil

Perfect For

• DIYers installing a system for large living rooms, basements, or workshops

• Upgrading an existing system with a new, high-capacity indoor unit

• Creating a custom installation with preferred components

• Homeowners seeking zoned comfort for large, open spaces

Ready to install high-capacity comfort yourself?
The MRCOOL DIY 36K BTU Air Handler delivers powerful performance, intelligent features, and the simplicity that defines the DIY experience. Add to cart and pair it with a compatible outdoor condenser and lineset to build your complete system.

🔗 Need the Complete Bundle?
For the easiest all-in-one solution, see our MRCOOL DIY 36K BTU Complete System Bundle, which includes this air handler, the matching outdoor condenser, pre-charged lineset, and all necessary cables in one ready-to-install kit.